Tilda Lindstam is carrying a mini Pashli satchel by 3.1 Phillip Lim.
You may find similar or bigger Pashli bags at following places :
at Net-a-porter
Mini Pashli leather and elaphe shoulder bag / The Pashli shark-effect leather trapeze tote
at farfetch
3.1 PHILLIP LIM Pashli satchel / 3.1 PHILLIP LIM Pashli Leather Satchel Bag
at thecorner
3.1 PHILLIP LIM Medium Leather Bag